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March 17, 2010 - The FDA has approved Esteem, a fully implantable hearing
aid with no visible external parts.

Esteem is approved for adults 18 and older with moderate to severe
sensorineural hearing loss. This is the kind of hearing loss caused by genetic
factors or by damage to the inner ear from noise, viral infections, or
aging.

In a clinical trial, the device worked better than external hearing aids for
56% of patients, worked as well as an external hearing aid for 37%, and worked
worse for 7%.

The most common side effects were caused by the surgery to implant the
device in the inner ear. Over 40% of patients had a taste disturbance, nearly
20% had imbalance or dizziness, and 7% had facial paralysis. Most of these side
effects got better within a year.

Another side effect may be wallet shock. The cost of the Esteem system is
$30,000. Normal hearing aids range in price from several hundred to several
thousand dollars.

But the Esteem system is radically different from hearing aids. It has three
parts:

The sensor detects vibrations coming into the ear and translates them to
electric signals.

The sound processor takes electric signals from the sensor
and amplifies them to compensate for an individual patient's hearing
loss.

The driver receives these enhanced electric signals and turns them back
into vibrations, which are transmitted to the inner ear and perceived by the
brain as sound.

A possible drawback to the device is that the battery can be replaced only
via a surgical procedure, which can be done under local anesthetic. The battery
lasts about 4.6 years if left on 24 hours a day, 6.6 years if left on 16 hours
a day, and nine years if left on eight hours a day.

The FDA approval has strings attached. Esteem maker Envoy Medical Corp. must
conduct two studies: a follow-up study to see what happens to the 61 patients
in the original study; and a new study of 120 Esteem recipients to assess the
incidence of facial paralysis a month after implantation and safety five years
after implantation.

"The approval of Esteem provides patients with an option to alleviate their
hearing loss by using a device with no readily visible external components,"
Jeffrey Shuren, MD, JD, director of the FDA's device center, says in a news
release.